The rod clamp fits ring-stand rods up to 1/2 inch or 12.7 mm in diameter. The rod clamp is included with all Vernier dynamics cart and track systems.

The discontinued Vernier Dynamics System (with metal carts) shipped after August 2011 also included the same rod clamp. The rod clamp shipped with the Vernier Dynamics System prior to August 2011 was smaller, and would fit rods up to 9 mm in diameter.